Palestinian Prime Minister Mahmoud Abbas (right) with US national security adviser Condoleezza Rice in the West Bank town of Jericho on Saturday. (AFP)

Gaza, June 29 (Reuters): The Palestinian militant groups Hamas and Islamic Jihad declared a three-month suspension of attacks on Israelis today, a move which could boost a fragile US-backed peace plan.

But Israel immediately dismissed the ceasefire as a “ticking bomb”, saying a truce would give the groups time to restrengthen.

The truce announcement followed word from Israel that it would start withdrawing forces from occupied Gaza territory tomorrow in return for Palestinian police assuming security control and preventing militant attacks on Israelis.

Both moves coincided with a visit by US national security adviser Condoleezza Rice, who held talks yesterday with Palestinian Prime Minister Mahmoud Abbas and today with Israeli leader Ariel Sharon.

The militants’ statement said: “We, the factions of the Palestinian resistance, signing this statement, declare the following initiative...the suspension of military operations against the Zionist enemy for three months....This initiative goes into effect from today.”

The truce was conditional on a “total cessation of all forms of Zionist aggression”, including Israeli military incursions, closures around Palestinian cities, a siege around the presidential compound of Yasser Arafat and “assassinations”.

Hamas and Islamic Jihad have killed hundreds of Israelis in suicide bombings since the start in September 2000 of a Palestinian uprising for statehood.

The mainstream Fatah faction, whose militant al-Aqsa Martyrs Brigades have also sent suicide bombers into Israel, did not sign the statement. But Fatah political leaders said a separate truce declaration was imminent.

Israel called the ceasefire an empty tactic aimed at giving the two militant groups breathing room in the face of a US diplomatic drive against them and Israeli attacks on senior militants.

“In the long term, this is a ticking bomb,” Israeli foreign minister Silvan Shalom told Israel’s Channel One television.

“I will repeat what foreign minister Silvan Shalom said two hours ago to US national security adviser Condoleezza Rice — this ceasefire is a ticking bomb because it actually maintains the infrastructure of terror,” Meir said.

Despite its dismissal of the truce, Israel’s withdrawal from Gaza could lead to a sharp curtailment of Israeli military activity against militants.

Security sources said Israel would cease lightning incursions and dismantle military checkpoints, which have paralysed Palestinian life in Gaza.

Palestinian police conducted exercises in parts of the Mediterranean desert strip to prepare for the security handover.

The West Asia peace plan prescribes the creation by 2005 of a Palestinian state in the West Bank and Gaza Strip alongside Israel, which occupied both areas in the 1967 war. The plan, known as the “road map”, was affirmed by Israel and the Palestinians at a June 4 summit in Aqaba, Jordan attended by President George W. Bush.

The US has said a ceasefire by militant groups would be a good first step in bolstering the plan, but has backed Israel in calling for Abbas to dismantle them as mandated by the road map. Israel says it is bound only to agreements with the Palestinian Authority and if it does not swiftly disarm and jail militants, it would resume hunting them down. Palestinian officials fear that trying to wipe out the popular Islamic factions could provoke a civil war.